A tire valve for automobiles comprises a valve metal body with an elastic body around the metal body. The top thread of the metal body connects to a protective cap and a valve core is set inside the metal body. The valve is mounted on a rim with its end inside the tire. At the present, it is required for some automobiles to monitor the tire pressure when being driven. Consequently, an electronic box of a tire pressure monitoring system, mounted inside the tire, is connected to the valve for real-time examination. At present, a bolt hole is placed on the metal body of the valve, the metal body uses an internal thread to connect the electronic box of the tire pressure monitoring system. However, such connection structure is likely to become loose when tires are running at a high speed.